Longest charting history

[Broken_Arrow]

You can never trust a computer for such a long term.

Your chart data seems to be just as, or more important to you than your logged data. If that's the case, I would periodically Invoke the Get Image method and capture the chart into pictures in an array. You then can just scroll back through the array and look at, for example 1280 data buckets at a time on separate pictures of charts, while your "live" chart is up there chugging away on the current 1280 points.

[Broken_Arrow]

Example of what it might look like...

[labviewleroy]

niquist, thats not what i mean. My point is there is no reason to hold 2.5 million points if im only gonna see 1280 of them 

[labviewleroy]

thanks for the reply and the pics. I prefer not to do this either it seems too tedious. As far as losing information and not trusting the computer thats not a concern of mine. I can overcome this by writing to a file and if need be I can always recall that information.

The way I see it is any one time on a screen I can only see 1280 pixels. Why store more than that in the chart history? 

[Joseph_Loo]

You can adjust the chart to display the entire month work. That is part of the magnifier feature on chart.

[Tori.M]

Hi Labviewleroy,

It was my understanding before that you wanted to plot the full month's data on one chart. Is it possible for you to clarify whether this is the case please?

As you've identified, due to the lack of pixels in your screen, you won't be able to display the full month at once. However still set your "Chart history length" to hold the full month's data (i.e. 2.7million) and then set your 'X Axis' from 0 to 1279, with an X- scrollbar (as shown in the example below) and you will be able to view the full month's data, but scrolling 1280 points at a time. The zoom function will allow you to zoom in and out of areas on the chart, or even show all of the points at once. It may be preferable to set your axis from 0-1000 initially, as this allows pixels for the border of the graph etc.

 

Hope this has helped to resolve your question!

[labviewleroy]

Hi Tori, 

Thank you for the explanation. To be specific what I actually want to do is graph a months worth of data. However, because I wont be exporting the data, I don't see a need in holding on to more than 1280 points (or however many pixels i have). I would be happy to simply compress a months worth of data onto one graph and hold on to only 1280 points at a time. 

[NIquist]

You still seem unclear on one important concept.  The chart will automatically compress your data for you so that a month of data can be shown in one chart.  Then if you use the chart tools to zoom in visually, the chart will display finer and finer amounts of detail by pulling the points from its chart history. That is the whole reason a chart has the option for a large history.  So you can see THE BIG PICTURE and the fine details in one display.

It sounded like that was what you wanted to do.  We were warning you that since the data points are not being saved to anyplace besides RAM you could lose your data in the case of a PC failure.  Hence, the recommendations to save to file while you're collecting.

[NIquist]

BTW Broken Arrow, I am definitely stealing your idea for using Get Image on charts.  It will be a great way to generate quick, overview test reports for users and bosses without offering them Too Much Information.

[labviewleroy]

so, is there a way to ONLY see the big picture? I dont carea bout zooming in to finer and finer details